Eigil aage hansen



E. A. HANSEN. LOW WATER ALARM APPARATUS FOR STEAM BOILERS. APPLICATION FILED 050.22, 19uA 1,312,175. Patented Aug, 1919.

gigi) Auge Hansen /A/I/E/I/o/sl L; Arron/IH EIGIL AAGE HANSEN, OF FREDERIKSBERG, NEAR COPENHAG-EN, DENMARK.

LOW-WATERALARM .APPARATUS FOR STEAMFBOILERS.

` Specification of Letters Patent.

Patented Aug. 5, 1919.

Application led December 22, 191'?. Serial No. 208.374.

To all whom t may concern:

Be it known that I, EIGIL AAGE HANSEN, a subject of the King of Denmark, residing at Frederiksberg, near Copenhagen, Denmark, have invented new and useful Improvements in Low-Water-Alarm Apparatus for Steam- Boilers; and I do hereby declare the follow ing to be a full, clear, and exact description of the same.

The present invention relates to an improvement in alarm apparatus for indicating low water in steam boilers. The apparatus comprises a casing connected with the water body of the boiler, which casing is normally filled with stagnant, relatively cold water, but when the water in the boiler falls below a predetermined level the casing is filled with hot steam, actuating a thermostatic device in the casing` to permit the steam to escape to a whistle or other signal apparatus.

The characteristic feature of the present invention is the use of a disk of thin metal or a diaphragm instead of the ordinarily used fusible plug or valve, which disk closes a small aperture and can be pierced by a pointed stylus or the like which is actuated by the thermostatic device.

The invention is shown in the accompanying drawing in a sectional view. a; designates the casing, Z9 a plug tightly screwed into the same and providedwith a stud c carrying the bimetallie spring el. The free end of the latter is positioned to actuate one arm of an angle lever e pivoted on the plug and the other arm of the lever is positioned to press a pointed stylus f or the like upward in a bore in the plug b as shown;v The whistle It ends in a sleeve which may be screwed over a nipple on the plug b and tighten akdisk g of thin lead plate or other suitable material firmly against the end of the nipple, so that the bore containing the stylus f is tightly closed.

If the spring al is heated and the metal which has the greatest expansion is on the outside of the same, the spring will cause the angle lever e to press Jthe stylus f upwardly, and the latter will pierce the lead plate so that the steam can flow to the whistle.

The bimetallic spring, shown as one form of thermostatic means which may be used, has the advantage that it occupies but a small space so that the apparatus is small and compact in construction; but the invention is not limited to the use of such a spring, as I may employ any suitable means which directly or indirectly causes the thinplate to be perforated when such means is exposed to heat. v

As the opening which is to be closed need only be some few millimeters in diameter,

ferred to an apparatus with a valve, which must close very tightly and which may stick or fail to operate if permitted to remain in the same position for a considerable period.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patent in U. S. A.- y

1. An alarm device for indicating low water level in a boiler, comprising a casing adapted to communicate with the water space of a boiler, said casing having a passage therethrough, an alarm device secured to said casing over the passage therein, a frangible diaphragm adapted to normally close communication between the casing and the alarm device, thermostatic means within the casing and means under control of said thermostatic means and adapted to be projected against and to disrupt said' frangible diaphragm upon the presence of unduly high temperatureswithin the casing.

2. In a device for indicating low water level in a boiler the combination of a casing adapted to communicate with the Water space of a boiler said casing having a passage adjacent to one end thereof, an alarm device engaging said casing over the passage therein, a frangible diaphragm closing said passage and interposed between the casing and the alarm device, a rod movable in said passage and adapted to be projected against and to disrupt said diaphragm, a pivoted double arm lever having one arm in position to engage said rod, and a thermostatic device engaging the other arm of said lever and for moving the same about its pivot.

In testimony whereof I have affixed my signature in presence of two witnesses.

EIGIL AAGE HANSEN.

Witnesses:

G. STUB, I. KNUDsEN.

Genies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents. Washington, D. C. 

